• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1163-1168
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• 2011

Most transformers use insulating and cooling fluids derived from petroleum crude oil, but mineral oil has some possibility of environmental pollution and fire with explosion. vegetable oil fluids extracted from seed has superior biodegradation and fire-resistant properties including an exceptionally high fire point enhancing fire safety. In this study, it is aimed at the practicality of substituting natural ester dielectric fluid for mineral oil in liquid insulation system of transformers. As a rise in coil winding temperature has a direct influence on transformer life time, it is important to evaluate the temperature rise of coil winding in vegetable oil in comparison with mineral oil. Four transformers for the test are designed with 10KVA, 13.2KV, one phase unit. The temperature are directly measured in insulating oil of these transformers with the two sorts of natural ester and mineral oil dielectric fluid respectively. Experiment for aging carry out two means. First means remained $120^{\circ}C$ that transformer of mineral oil were operated at 185% load. Second means is that insulating oils of two natural ester and mineral oil were aged by thermal cycles repeating from $30^{\circ}C$ to $120^{\circ}C$. For the heating, Transformers were operated at 185% load. For the cooling, cooling system was operated in the chamber. Samples were analyzed at 42, 63, 93, 143, 190, 240 300cycles. Analysis contents are dielectric strength, total acid value. Mineral oils compared results of first means with results of second means. And compared two sort natural esters respectively with mineral oil in second means.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.7
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• pp.1028-1034
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• 2015

General composition and cholesterol contents of chicken 4 parts (breasts, thighs, legs without skin, and wings with skin) were analyzed. Fatty acids, amino acids, and mineral contents of breasts and thighs were also analyzed and compared with sirloin parts of beef and pork. Lipid contents of chicken parts (1.2% in breasts, 2.8% in thighs, and 14.9% in wings) were lower than those of beef and pork. Protein contents of chicken parts (22.9% in breasts, 19.7% in thighs, and 17.6% in wings) were higher than those of beef and pork. Cholesterol contents of chicken parts (99.0 mg% in wings, 80.8 mg% in thighs, and 56.7 mg% in breasts) were higher than those of beef and pork. However, saturated fatty acid contents of chicken (31.6~32.9%) was lower than those of beef (40.8%) and pork (42.7%). In the meanwhile, unsaturated fatty acid contents of chicken (67.1~68.4%) was higher than those of beef (59.2%) and pork (57.3%). Essential fatty acid contents of chicken (16.6~16.9%) were 1.6 times as high as that of pork (10.4%) and 5 times as high as that of beef (3.9%). Major amino acids composition were glutamic acid, aspartic acid, lysine, and leucine. Ten essential amino acid contents were 11,860 mg% in breasts and 10,454 mg% in thighs, and the ratio of essential amino acids (41.7~44.1%) was similar to those of pork and beef. Mineral contents of chicken were similar to those of pork and beef despites of slight different mineral contents in thighs and breasts.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.4
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• pp.783-794
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• 1994

Recently, several failure cases of concrete structures during construction have been reported. The main reason for these failures is attributed to the poor quality of concrete during construction. It is, therefore. necessary to develop and use high quality concrete. The purpose of the present study is to explore the characteristics of superplasticized concrete, especially the effects of mineral admixtures on the fluidity and strength characteristics of high performance concrete. The mineral admixtures considered in the present study are fly ash, blast furnace slag and silica fume, respectively. The major test variables include the amount of these mineral admixtures, cement contents and water-cement ratios. The compressive strengths for various cases were measured and reported. Optimum contents of mineral admixtures for strength development were derived. The corrosion phenomena of reinforcements embedded in various concrete specimens have been also studied. The present study provides useful basis to apply high-performance concrete to actual structures.

• The Journal of the Korea Contents Association
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• v.9 no.5
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• pp.214-223
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• 2009

In this study we investigated the impact of exercise program through the grip strength, the balance and the bone mineral density of elderly women in rural community. A total of number 56 elderly women were divided into two groups, the experimental group(n=33) and the control group(n=23). The experimental group participated exercise program during 13 weeks from 3 Oct to 29 Decem in 2005, twice a week 60 minutes per session. Among the experimental group, 33 people who participated over 20 times exercise program were chosen as the subjects of analysis. The results of this study were as follows: The grip strength was significantly increased in the experimental group compared with the control group(p<0.05). The Timed up and go test and Bone Mineral Density were significantly increased in the experimental group compared with the control group(p<0.01). In conclusion, there has been a substantial improvement in 13 weeks by exercise program is recommended to elderly women in aspect of increasing the grip strength, the balance and the bone mineral density.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.19 no.2
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• pp.123-129
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• 2016

Purpose: This study was performed to evaluate the dietary nutrient intake status and hair mineral content of Korean young children. Methods: Fifty-five children who visited Seoul National University Bundang Hospital were divided into three groups by age: infants, toddlers, and preschoolers. The 24-hour recall method was used to collect the food intake data of the subjects. Hair mineral analysis was conducted using a Mass Spectrometer. Serum iron, ferritin, and calcium were also measured. Results: The mean energy intakes of the subjects were 730.3 kcal, 994.3 kcal, and 1,482.9 kcal for each age group. The mean percentage of energy intake compared to recommendation was 101.4% and was not different by age group. Toddlers of 37.8% and preschoolers of 54.5% consumed less than the Estimated Average Requirement (EAR) of calcium. Infants of 28.6%, toddlers of 10.8% and preschoolers of 9.1% consumed less than the EAR of iron. In the case of zinc, copper, and selenium, only 0% to 5% of toddlers and none of the preschoolers consumed less than the EAR of those minerals. The hair calcium, iron and copper concentrations were lower in toddlers and preschoolers than those in infants. Serum calcium levels of preschoolers were significantly lower than those of infants, whereas serum iron and ferritin levels were not. Conclusion: Hair calcium, iron, and copper concentrations were significantly lower in toddlers and preschoolers than in infants. Insufficient dietary intake of calcium and iron seems to be related with decreased hair mineral contents in young children.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.4
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• pp.257-263
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• 1994

The experiment was canied out to investigate the effects of cutting frequencies (3, 4 and 5 cuts per year) in relation to fertilization of mineral nitrogen on crude protein yield and the contents of crude protein and acid detergent fibre in orchardgms(Dacty1is glomerata L.). Tne results are as follows : 1. The content of crude protein increased according to the increase in cutting frequency and showed the highest in the 1st cut in all treatments. At 4 and 5 cutting frequencies per year, the content of crude protein increased in a large extent according to the increased fertilization of mineral nitrogen. However at 3 cutting frequency, the content of cmde protein appeared higher for no application of mineral nitrogen than for the treatments with fertilization. 2. 'Ihe content of acid detergent fibre(ADF) was considerably reduced at 4 and 5 cutting frequencies and in all treatments, the lowest were recorded in the 1st cut or in the last cut. At 3, 4 and 5 cutting frequencies, the highest ADF were shown in the 2nd cut, 3rd cut and 3rd cut respectively. However, the general trend was that the content of ADF was greatly reduced according to increased level of mineral nitrogen fertilization. 3. The yeild of cmde protein was the highest at 5 cutting frequency(l.2 ton DMIha) and it indicated that the yield of cmde protein increased in accordance to the increase in fertilization of mineral nitrogen and cutting frequency. 4. In all treatments, positive correlation(p<0.001) between the yeilds of crude protein and annual dry matter yield appeared. Negative correIation(p

• Proceedings of the Korea Contents Association Conference
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• 2016.05a
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• pp.373-374
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• 2016

본 연구는 외상으로 인해 치수괴사가 나타난 미성숙 영구전치에서 한국에서 새롭게 개발된 MTA를 이용한 치근단형성술을 시행한 후 비교적 장기간 그 예후를 살펴본 결과를 보고하고자 한다.

• Economic and Environmental Geology
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• v.29 no.5
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• pp.545-559
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• 1996

Rare metal (Nb-Zr-REE) ore deposits are located in the Chungju area. Geotectonically, the rare metal ore deposits are situated in the transitional zone between Kyeonggi massif and Okcheon belt. The rare metal deposits are distributed in Kyemyeongsan Formation which consist of schist and alkaline igneous rocks. Alkali granite has suffered extensive post-magmatic metasomatism and hydrothermal processes. The ore contains mainly Ce-La, Ta-Nb, Y, Y-Nd, Nd-Th group minerals. More than 15 RE and REE minerals are found in the ore deposits. Allanite, one of the Ce-La rich REE minerals belonging to the epidote group, is the most common mineral in the studied area. The allanite- bearing rocks may be devided into seven types by features of occurrence and mineral associations; zircon type (ZT), allanite-vein type (AT), feldspar type (KT), fluorite type (FT), quartz-mica type (QT), iron-oxide type (MT), and amphibole type (HT). The allanite veins (AT) and zircon rich rocks (ZT) contain the highest total REE contents. Differences in REE abundance can be interpreted in terms of varying portions of magmatic hydrothermal fluid. Petrographical and chemical data are presented for allanites which were collected from different types. The allanites show wide variations in optical properties, due in part to differences in their chemical composition (depending on the types) and to the degree of crystallinity of the individual specimens. Allanite metamicts in biotite are generally surrounded by well developed pleochroic haloes. Usually, allanite is accompanied by zircon and other REE-bearing minerals. CaO and total REE contents $({\sum}RE_2O_3)$ range from 9.29 to 18.79% and 11.66 to 26.31%, respectively. Also, SiO, (28.87~32.61%), $Al_2O_3$ (8.30~16.88%), and $Fc_2O_3$ (16.74~24.38%) contents show varying contents from type to type. The ${\sum}RE_2O_3$ of allanite has positive relationships with $Fe_2O_3$ and negative relaton with CaO, $SiO_2$, and $Al_2O_3$ Backscattered electron microscope images (BEl) of allanite shows that the its mineral composition and texture is very complex. The allanite-bearing hosts show distinct light REE enrichment with strong negative Eu anomaly except for HI. The HT has an almost flat REE distribution pattern with a small negative Eu anomaly. The chemical variation of the allanites with occurrences and mineral association can be related to condition of temperature and oxidation states in precipitation environment.

• The Journal of Engineering Geology
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• v.31 no.2
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• pp.187-197
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• 2021

Clay mineral content of weathered zone is a key parameter for landslide studies. Electrical resistivity tomography is usually performed to delineate the geometry of complex landslides and to identify the sliding surface. In clay-bearing weathered zone, parallel resistivity Archie equation is employed to investigate the effect of conductivity added (resistivity reduced) by clay minerals of kaolinite and montmorillonite, which is dependent on their specific surface area and cation exchange capacities (CEC). A decrease of overall resistivity and apparent formation factor is observed with increasing pore-water resistivity, significantly in montmorillonite. Formation factor is found decreased with increasing porosity and decreasing cementation factor. Parallel Archie equation was applied to the electrical resistivity data from the test area (Sinjindo-ri, Taean-gun, Chungcheongnam-do, Korea) which experienced land creeping in the year of 2014. A panel test with varying clay-mineral contents provides the best fit section when the theoretical section constructed with the assumed contents approaches the field section, from which the clay-mineral content of the weathered zone is estimated to be approximately 10%. Resistivity interpretation schemes including the clay mineral contents for land creeping studies explored in this paper can be challenged more when porosity, saturation, and pore-water resistivity are provided and they are included in the numerical resistivity modeling.

• Journal of Society of Preventive Korean Medicine
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• v.17 no.3
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• pp.177-185
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• 2013

Objective : Eucommiae Cortex is bark of Eucommia ulmoides Oliver, a deciduous tree native to China. Today, teas or herbal drugs made from E. ulmoides leaves are widely consumed as a healthy food especially in Eastern Asia including Japan, China and Korea. This study was aimed to verify the extraction efficiency of bioactive compounds from Eucommiae Cortex depending on characteristics of decoction water. Method : Six types of decoction water with various origin were prepared and the contents of minerals in water were analyzed by ICP-AES and ICP-MS. The contents of extracted bioactive compounds were analyzed by HPLC and the relationship between mineral contents and extracted bioactive compounds in the decoction water were analysed by multiple factor analysis. The decoction waters could be classified in three groups by hierarchical cluster analysis. Result : Extracted amounts of compounds in Eucommiae Cortex showed a positive relationship with Na, Si, K concentration in decoction water, while a negative relationship with Ca, Mg concentration. Conclusion : The study proved that the minerals in water influenced the extraction efficiency of bioactive compounds from Eucommiae Cortex.